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Mind and Life Institute Research Grants
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Training and Studying the Mind: Toward an integration of Buddhist contemplative practices and neurosciences.
General purposes of the research project:
The general purpose of this research project is to gain new insights about the impact of meditation on basic affective and cognitive functions and on the brain mechanisms that subserve these processes. In addition, the research is designed to foster an understanding of the nature of conscious experience. Some of the positive mental attributes that are voluntarily cultivated in Buddhist contemplative practices, such as compassion, have not been part of the Western neuroscientific study of emotion (see Davidson, 2002). This research seeks to make these positive mental attributes a focus of scientific study. In addition, by combining the rigorous direct examination of conscious experience that is cultivated by Buddhist contemplative practices with Western neuroscientific exploration of the neuronal and somatic embodiments of conscious states, new insights can be gleaned about the fundamental nature of consciousness (see Varela, 1996; Lutz et al., 2002).
Description of the research project:
This project involves the measurement of functional brain activity with brain imaging methods in highly trained Buddhist practitioners during various meditative states. These studies are currently in progress at the Keck Laboratory, University of Madison, Wisconsin and at LENA laboratory (CNRS, UPR 640), Hôpital de la Salpêtrière, Paris.
We are focusing on four mental states, well documented in Buddhist psychology and referred to as focused attention, open attention (or pure awareness), visualization and generation of compassion. These meditative techniques cultivate different mental faculties, some of which have received scant attention in the modern scientific literature.
- Focused attention (Samatha) or 'one-pointed concentration' involves sustaining attention upon an object without being distracted away from it
- Open attention (Rig pa'i cog bgzag) is a state of total openness in which the mind is not focused on something. It is unconcerned and unaffected by perceptions, recollections and imagination, yet there is no intent whatsoever to block or prevent them;
- Visualization consists of both the mental construction and mental viewing of highly detailed visual mental images;
- Compassion consists of the voluntary cultivation of a positive affective state that Buddhist practitioners consider essential to counteracting self-centered tendencies. It involves the generation of a state in which love and compassion permeate the whole mind, with no other consideration, reasoning or discursive thoughts.
In our preliminary pilot studies, we examined these states without any stimuli and during the presentation of visual images. Three non-invasive brain imaging techniques are used: namely high-density electroencephalography (EEG), magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI). EEG (Fig 1) and MEG (Figs 2-3) are two complementary techniques that measure, respectively, the magnetic induction outside the head and the scalp electric potentials produced by the electrical activity in neural cell assemblies.
  Figure 1: EEGFigure 2: MEG
 Figure 3: Generation of localized changes in magnetic and electrical fields by neural activation (image from Baillet S. et all. 2001).
These two techniques have excellent temporal resolution in the millisecond range that allows us to explore the fine temporal dynamic of neural processes during these meditative states. fMRI works at a much slower temporal scale (at the order of hundred of milliseconds) but is capable of producing spatial resolution as high as 1-3mm. This technique records the hemodynamic changes during neural processes. As neurons become active, they induce very localized changes in blood flow and oxygenation level that can be imaged as a correlate of neural activity. fMRI provides anatomical and functional information about the cortical and subcortical structures activated during a particular mental state (Figs 4-5).
 
Figure 4: MRI scanner and image of brain structure.
Figure 5: Examples of functional activation (orange and red) superimposed upon images of brain structure made with fMRI.
By combining the spatial and temporal resolutions of these techniques we hope to identify the neural structures activated during these states and characterize the neural signature of their dynamical coordination. Indeed, it is a well-accepted fact that in the brain any complex mental process (such perception, action, imagination, emotion.) is characterized by the simultaneous activity of distributed brain regions that are functionally specialized and constantly interacting. Any assumption about the substrate of a moment of consciousness must therefore account for the coordination of these different components necessary to produce global brain activity that is transiently unified.
A possible mechanism for this coordination is neural synchrony because of its putative role in the constitution of the transient networks that integrate distributed brain processes into highly ordered cognitive functions (as reviewed in Engel el al. 2001 and Varela et al. 2001). Such coherent temporal patterns may represent the neural counterpart to subjective experience and can be estimated with recent mathematical tools from the EEG/MEG data (Fig 6). Our working assumptions are thus, firstly, that specific meditative states can be correlated with specific dynamical neural signatures in these synchrony patterns and, secondly, that such on-going synchrony patterns occurring during a meditative state can constraint, in a reliable way, the temporal structure of the neural responses to sensory stimulation.
Figure 6: Red color coding indicates on the scalp distribution an increase of local synchronization recorded by a single electrode (time-frequency power emission). Black lines correspond to long-distance phase synchrony that occurs when two neural populations recorded by two distant electrodes oscillate with a precise phase relation that remains constant during a certain number of oscillation cycles (Lachaux et all. 1999). The study of synchrony and non-linear dynamics in this research will use several algorithms developed at the LENA laboratory, CNRS UPR 640, Paris. For more information contact Jean-Philippe Lachaux from the Neurodynamical team.
Scientific and Buddhist team of investigators:
Richard J. Davidson, Director, W.M. Keck Laboratory for Functional Brain Imaging and Behavior, University of Wisconsin-Madison
Antoine Lutz, Post-doctoral fellow, W.M. Keck Laboratory for Functional Brain Imaging and Behavior, University of Wisconsin-Madison
Matthieu Ricard, Shechen Monastery, Katmandu, Nepal
Francisco Varela, PhD (1946-2001) was deeply involved in the initiation of this project and we dedicate our efforts to his memory.
References:
Davidson, R.J. (2002). Toward a biology of positive affect and compassion. In R.J. Davidson and A. Harrington, (Eds.), Visions of Compassion: Western Scientists and Tibetan Buddhists Examine Human Nature. New York: Oxford University Press.
Engel, A.K., Fries, P., and Singer, W. 2001. Dynamic predictions: oscillations and synchrony in top-down processing. Nat Rev Neurosci, 2: 704-16.
Lutz, A., Lachaux, J.P., Martinerie, J., and Varela, F.J. 2002. Guiding the study of brain dynamics by using first-person data: Synchrony patterns correlate with ongoing conscious states during a simple visual task. Proc Natl Acad Sci U S A, 99: 1586-91.
Varela, F. 1996. Neurophenomenology : A Methodological Remedy to the Hard Problem. Journal of Consciousness Studies, 3: 330-50.
Varela, F., Lachaux, J.P., Rodriguez, E., and Martinerie, J. 2001. The brainweb: phase synchronization and large-scale integration. Nat Rev Neurosci, 2: 229-39.
© Copyright 2007 Mind and Life Institute, Boulder, CO, USA. All rights reserved.
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